GSXR Head Install

[Roger P.]

Ok, so I won a rocker type 1127cc gsxr1100 head on the 'bay, complete with valves and cams with slotted wheels. From what I gather, this is a pretty straightforward install, with some minor mods to route the oil, seal various leak points, and remove the SACS system. I think I might be getting a set of 36mm carbs of a 1990 Katana 750. Considering that I will be keeping stock displacement for now, do you think simply setting up these carbs to GSXR1100 spec will get me in the ballpark jetting wise, considering I will have to go the pod route? I guess an aftermarket 4-1 pipe will be required to make max use of the upgraded breathing capabilities?

Also, there is an option for a guy locally to do a swap for some 33mm Mikuni smoothbores for my stock carbs. Are these carbs a bit cranky for street use, or would they be a better performance carb?

 

[rapidray]

If you want help with the swap, call me at 714-356-7845 as I do about 10 of these a year. Ray.

 

[Roger P.]

Thanks Ray, you are very generous with your time. I am still in the parts acquisition phase of all this, slowly transitioning into the "what the hell am I doing phase". once I start to get my hands dirty, I am sure I will be bugging everyone with all sorts of questions.

 

[davel]

If you want help with the swap, call me at 714-356-7845 as I do about 10 of these a year. Ray.

Ray, Are there any advantages to running the oil cooled head over the 16V air cooled head on a street bike? And, any concern with the GSXR head overheating without the cooling oil?

Thanks,
Dave

 

[rapidray]

Roger, you need to order a set of APE 1150 cylinder studs. Dave, call me at 714-356-7845. It is just easier for me to deal with this over the phone. The GSXR head works well on the street but you need to do some things. Ray.

 

[motocycle shawn]

ray

ray

ray can you send me a pm about this my phone is off right now.
but i would like to know more about this swap before i put the 1166 topend back on. and why are the cam gears bigger on a 750 vs my 1166?

 

[posplayr]

ray can you send me a pm about this my phone is off right now.
but i would like to know more about this swap before i put the 1166 topend back on. and why are the cam gears bigger on a 750 vs my 1166?

Shawn, I think that is Ray's point it is too much time/work to try and write everything he knows into a pm. Give him a call you will not regret it. I had dinner with him last nite ; he is on the road the next couple of days.
Jim

 

[RacingJake]

Dot head on a GS

Dot head on a GS

Here's the biggies

I'm using 13-1 pistons and had to mill the sides of the dome's to fit the small Dot head 20cc or is it 22cc ??? chamber. I can set the cranking compression as high as 265 psi or back it down close to 200 just by degreeing the intake cam.

You use the GS cam sprockets with the GSXR cams and GSXR 1100 front cam guide.

28mm brass plugs to plug the oil return ports

I use small 0-rings here and force them into the block cause the head has a oil drain port on the front center studs. If you have a solid block then nothing needs to be done.

Then after the head is installed RTV any exposed holes

 

[posplayr]

Thanks RacingJake. That was very useful pic. I did a little reseach on a DOT head. What compression pistion are you running and where do you end up with the GS head?

For everybody else, here is a lill splaination on GSXR heads I found.

http://www.gixxer.com/forums/showpost.php?p=4358285&postcount=2

Most of this is a Oil cooled GSXR discussion

Re: Which is the "right" head?
the "Dot" head is a 1988 to 1989 748cc 'short stroke' motor head.

It has the same cam chain tunnel as an 1100 head.

The intake ports are raised about 10mm from the long-stroke 750 and 1100 heads. This makes it flow better in stock form.

The combustion chamber is about 20cc, or about 4cc less than the 1100 heads. This gives a boost in compression to the stock 1100 motor.

However, there are some problems with the head:

- The carb boots are unique to this head and only fit the 36mm slingshot carbs. You can't use 38mm carb boots on this head.
- The combustion chamber won't work very well with aftermarket pistons because you compression ratio will be way too high. It will bump it up 1-2 points. If you are already running a 1300cc+ motor, the only pistons I know of are already 12.0:1 CR, and you won't be able to run the dot head without some kind of crazy race gas.

What you want is a 'regular' 1100 screw adjuster head. The 1986-90 1100 heads and the 1996-2006 Bandit 1200 head are all pretty much the same thing. Any of them can be ported and have big valves installed (you'll need it for a 1300 motor!).

Oh the other problem with the dot head, especially in a 7/11, is that it raises the carbs so high that they run into the frame. They also make it impossible to run air filters.

 

[rapidray]

The "dot" heads are a 22cc chamber & the GSXR 1100 heads are 26cc chamber. The GS1100/1150 heads are 27cc chambers. One thing I do different than Ryan is to drill & tap the exposed holes in the block & install plugs instead of using RTV or any sealant that could come loose & get into the motor in any way. Ray.

 

[posplayr]

One thing I do different than Ryan is to drill & tap the exposed holes in the block & install plugs instead of using RTV or any sealant that could come loose & get into the motor in any way. Ray.

That would make me feel better from a longevity standpoint.

 

[RacingJake]

Thanks RacingJake. That was very useful pic. I did a little reseach on a DOT head. What compression pistion are you running and where do you end up with the GS head?

I figure I'd give my 2 cents until Ray got back

I have 1166, 13-1 Wiseco pistons and cranking compression around 220 PSI. For me that's around 60 thousand V-P clearance. Add just a small 36 shot of nitrous and you better hold on cause she'll haul my 250 lb butt down the 1/8 at 124 mph.

 

[posplayr]

I figure I'd give my 2 cents until Ray got back

I have 1166, 13-1 Wiseco pistons and cranking compression around 220 PSI. For me that's around 60 thousand V-P clearance. Add just a small 36 shot of nitrous and you better hold on cause she'll haul my 250 lb butt down the 1/8 at 124 mph.

Holey Crapp ........

 

[RacingJake]

Ok, so I won a rocker type 1127cc gsxr1100 head on the 'bay, complete with valves and cams with slotted wheels. From what I gather, this is a pretty straightforward install, with some minor mods to route the oil, seal various leak points, and remove the SACS system. I think I might be getting a set of 36mm carbs of a 1990 Katana 750. Considering that I will be keeping stock displacement for now, do you think simply setting up these carbs to GSXR1100 spec will get me in the ballpark jetting wise, considering I will have to go the pod route? I guess an aftermarket 4-1 pipe will be required to make max use of the upgraded breathing capabilities?

I've always ran a 160 mikuni jet in my 34 oem carbs and 38mm cv carbs, anything smaller I could feel the bike nose over.